Sand traps



Feb. 26, 1957 $AAR| ETAL 2,783,070

SAND TRAPS Filed Jan. 8, 1954 .SAND TRAPS Frank Saari, Oak Park, and Grant V. W. Roth, Evanston,

111., assignors to Monarch Equipment Corporation, Chicage, 11]., a corporation of Illinois Application January 8, 1954, Serial 'No. 403,012

4 Claims. (Cl. 291-11) The invention relates to sand traps for delivery sand to railway rails.

One object of the invention is to provide improved means for varying the volume of sand delivered to the rails for most efiicient braking action.

Another object of the invention is to provide a trap which includes an air jet for discharging sand onto the rails and an air jet for producing turbulence in the sand retaining chamber, with valve means whereby the pressure ratio of said jets may be varied, to accurately control the volume of sand discharged-for delivery to the rails.

Another object of the invention is to provide a sand trap which is simple in construction and efiicient in operation.

Other objects will appear from the detailed description.

The invention consists in the several novel features hereinafter described and more particularly defined by claims at the conclusion hereof.

In the drawings:

Fig. 1 is a longitudinal sectionof asand trap embodying the invention;

Fig. 2 is a section taken on line 2--2 of Fig. 1;

Fig. 3 is a section taken on line 33 of Fig. 1; and

Fig. 4 is a section taken on line 4-4 of Fig. l.

The invention is exemplified in a trap which comprises a casing or housing generally designated 9, provided with a vertical inlet leg 10, the upper end of which is communicatively coupled to a pipe or fitting 11 which is connected to receive sand from the usual dome (not shown). The lower end of leg communicates with a passage 12 through which the sand flows to a laterally extending chamber 14. A discharge pipe 15 for delivering sand to the rails is connected to a horizontal conduit 16 in the casing, which is coaxial with said pipe and is communicatively connected to chamber 14 by a vertical passage 17. The passage 12 is related to the chamber 14 so that sand flows into chamber 14 to retain a body of sand to the dotted line x in Fig. l. A screw plug 18 is provided at the lower end of leg 10 for access to sand which may become clogged in leg 10.

A pipe 20 is suitably connected to a supply of compressed air, extends across the inlet leg, is screw-threaded to a wall 21 of the casing over the chamber 14 and communicates with a cylindrical duct 22 which is coaxial with conduit 16. A jet of air passing from duct 22 into and through conduit 16 is adapted to siphon sand from chamber 14 through passage 17 and project it into pipe 15. A port 24 in the top wall 21 between duct 22 and chamber 14 is adapted to deliver air from duct 22 into chamber 14 for producing turbulence of the sand so the sand will be responsive to siphonic action from conduit 16.

The conduit 16 into which air flows from duct 22 is disposed above and co-related to the chamber 14 so that the air flow through conduit 16 and over passage 1'7 will not siphon static sand from chamber 14 so that the nited States Patent 0.

2,783,070 Patented Feb. 26, 1957 2 discharge of sand from conduit 16 is responsive to the turbulence in said chamber.

A screw 23, which is threaded to the casing 9 and functions as a valve, is adjustable across the duct 22 for variably controlling the pressure of air delivered into conduit 16. The port 24 remains in constant communication with duct 22. A head 26 is provided on the upper end of valve 23 for adjusting it in the casing and a lock nut is adapted to secure it in its adjusted position. Adjustment of valve 23 varies the pressure ratio in the discharge conduit 16 and in the chamber 14. The amount of sand discharged is variably responsive to changes in the pressure ratio in chamber 14 and conduit 16. For example, assuming the valve 23 to be fully open, the full blast of .air from duct 22 will be discharged into conduit 16, and there will be substantially no air flow through port 24 into chamber 14 and no turbulence in the sand in said chamber, so that the air fiow in conduit 16 will not siphon the sand into conduit and substantially no sand will pass into the conduit 16 or be delivered to the pipe 15. Further assuming the valve 23 to be fully closed, no air will pass directly from duct 22 to discharge conduit 16, and air under a high pressure will pass through port 24 and produce such high turbulence and pressure in chamber 14 that an excessive amount of sand will be .discharged through passage 17 and conduit 16 into the pipe 15. When the valve 23 is set in different intermediate positions, the pressure ratios in chamber 14 and conduit 16 will be varied to variably control the discharge of sand according to the setting of said valve.

In the sanding art, a desideratum is to deliver sufficient sand to the rails to produce a'certain degree of adhesion, and a limited degree of slippage for most efficient braking action, by the adjustment of the valve 23 to vary the ratio-of the pressureof air from supply duct 22 and port 24 to the chamber 14, and the pressure of air in conduit 16. The volume of sand for most efiicient braking effect may be accurately achieved.

In operation, the valve 23 will be set to distribute the air from duct 22 to proportion the flow of air to the conduit 16 and to the port 24, so that air under pressure will flow through port 24 to produce the necessary turbulence in the sand in chamber 14 and the air flow across passage 16 will siphon the desired amount of sand from chamber 14 through passage 17 and discharge it through pipe 15 to the rails.

By changing the setting of valve 23 to decrease the flow and increase the velocity of air through conduit 16, the flow and pressure of air passing via port 24 into chamber 14 and the turbulence of the sand produced in chamber 14 will be increased with a resultant increase in the flow of sand to the discharge pipe 15. By changing the setting of valve 23 to increase the flow and decrease the velocity of the air through conduit 16, the pressure'of air passing into chamber 16 and the turbulence of the sand produced in chamber 14 will be decreased, with a resultant decrease in the volume of sand delivered to the discharge pipe. In this manner, the sand trap may be adjusted to achieve the degree of adhesion of the sand to the tracks and wheels for most eflicient braking efiect of the vehicle.

The invention exemplifies a sand trap which is adjustable for the delivery of sand to the rails for producing optimum adhesion for etficient braking effect, and is simple in construction.

The invention is not to be understood as restricted to the details set forth, since these may be modified within the scope of the appended claims without departing from the spirit and scope of the invention,

Having thus described the invention what we claim as new and desire to secure by Letters Patent is:

l. A trap for sanding rails, comprising: a casing including a vertically extending leg having its upper end connected to receive sand from a dome, a chamber at one side of and extending substantially perpendicular to and communicatively connected to the lower end of, the leg,

a discharge conduit having its axis substantially parallel and vertically offset relatively to said chamber, and having its inner end communicatively connected to said chamber, and its outer end connected to deliver sand to the rails, means for supplying compressed air to the discharge conduit including a duct coaxial with said discharge conduit for siphoning sand from the chamber into the discharge conduit, a port between the compressed air conduit and said chamber for directing compressed air to produce turbulence in said chamber, and valve means in said air supply conduit for varying the Flow of air to the discharge conduit.

2. A trap for sanding rails, comprising: a casing including a vertically extending leg having its upper end connected to receive sand from, a dome, a chamber at one side of and extending substantially perpendicular to and communicatively connected to the lower end of, the leg, a discharge conduit having its axis substantially parallel and vertically offset relatively to said chamber, and having its inner end cornmunicatively connected to said chamber, and its outer end connected to deliver sand to the rails, means for supplying compressed air to the discharge conduit including a duct coaxial With said discharge conduit for siphoning sand from the chamber into the discharge conduit, a port between the compressed air conduit and said chamber for directing compressed air to produce turbulence in said chamber, and valve means in said air supply conduit for varying the flow of air to the discharge conduit, said inlet leg, chamber, discharge conduit and air supply duct being formed in integral portions of the casing.

3. A trap for sanding rails, comprising: a casing including a vertically extending leg having its upper end connected to receive sand from a dome, a chamber at one side of and extending substantially perpendicular to and communicatively connected to the lower end of, the leg, a discharge conduit having its axis substantially parallel and vertically offset relatively to said chamber, and having its inner end communicatively connected to said chamber, and its outer end connected to deliver sand to the rails, means for supplying compressed air to the discharge conduit including a substantially straight duct in the casing coaxial with the discharge conduit and a pipe section extending across the inlet leg coaxially with and connected to the inner end of said duct, 21 port between said duct and the chamber for directing air to produce turbulence in said chamber, and valve means in said duct for varying the flow through said duct to said. discharge conduit.

4. A trap for sanding rails, comprising: a casing including a vertically extending leg having its upper end connected to receive sand from a dome, a chamber at one side of and extending substantially perpendicular to and communicatively connected to the lower end of, the log, a discharge conduit having its axis substantially parallel and vertically ofiset relatively to said chamber, and having its inner end communicatively connected to said chamber, and its outer end connected to deliver sand to the rails, means for supplying compressed air to the discharge conduit including a duct coaxial with said discharge conduit for siphoning sand from the chamber into the discharge conduit, a port between the compressed air conduit and said chamber for directing compressed air to produce turbulence in said chamber, and a screw valve in the casing having its axis perpendicular to the axis of and movable across the straight portion of said duct.

References Cited in the file of this patent UNITED STATES PATENTS 2,240,266 Nation Apr. 29, 194i 2,499,114 Saari et al. Feb. 28, 1950 2,638,369 Saari et al. May 12, 1953 

